1 /*

     2  * Copyright 2014 Google, Inc.  All Rights Reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    20  * or visit www.oracle.com if you need additional information or have any

    21  * questions.

    22  */

    23 

    24 /*

    25  * @test

    26  * @bug 8043354

    27  * @summary  bcEscapeAnalyzer allocated_escapes not conservative enough

    28  * @run main/othervm -XX:CompileOnly=.visitAndPop TestAllocatedEscapesPtrComparison

    29  * @author Chuck Rasbold rasbold@google.com

    30  */

    31 

    32 /*

    33  * Test always passes with -XX:-OptmimizePtrCompare

    34  */

    35 

    36 import java.util.ArrayList;

    37 import java.util.List;

    38 

    39 public class TestAllocatedEscapesPtrComparison {

    40 

    41   static TestAllocatedEscapesPtrComparison dummy;

    42 

    43   class Marker {

    44   }

    45 

    46   List<Marker> markerList = new ArrayList<>();

    47 

    48   // Suppress compilation of this method, it must be processed

    49   // by the bytecode escape analyzer.

    50 

    51   // Make a new marker and put it on the List

    52   Marker getMarker() {

    53     // result escapes through markerList

    54     final Marker result = new Marker();

    55     markerList.add(result);

    56     return result;

    57   }

    58 

    59   void visit(int depth) {

    60     // Make a new marker

    61     getMarker();

    62 

    63     // Call visitAndPop every once in a while

    64     // Cap the depth of our recursive visits

    65     if (depth % 10 == 2) {

    66       visitAndPop(depth + 1);

    67     } else if (depth < 15) {

    68       visit(depth + 1);

    69     }

    70   }

    71 

    72    void visitAndPop(int depth) {

    73     // Random dummy allocation to force EscapeAnalysis to process this method

    74     dummy = new TestAllocatedEscapesPtrComparison();

    75 

    76     // Make a new marker

    77     Marker marker = getMarker();

    78 

    79     visit(depth + 1);

    80 

    81     // Walk and pop the marker list up to the current marker

    82     boolean found = false;

    83     for (int i = markerList.size() - 1; i >= 0; i--) {

    84       Marker removed = markerList.remove(i);

    85 

    86       // In the failure, EA mistakenly converts this comparison to false

    87       if (removed == marker) {

    88         found = true;

    89         break;

    90       }

    91     }

    92 

    93     if (!found) {

    94       throw new RuntimeException("test fails");

    95     }

    96   }

    97 

    98 

    99   public static void main(String args[]) {

   100     TestAllocatedEscapesPtrComparison tc = new TestAllocatedEscapesPtrComparison();

   101 

   102     // Warmup and run enough times

   103     for (int i = 0; i < 20000; i++) {

   104       tc.visit(0);

   105     }

   106   }

   107 }